* refactor RedirectHandler
- `redirectState` is no longer a property of `HTTPClient.Request`. RedirectHandler now stores this state directly and therefore no longer optional.
- we no longer count the number of allowed redirects down. Instead the number of redirects is dervied from `self.visited.count` and we compare it to the maxRedirect to check if we git the limit.
* `HTTPClient.Configuration.RedirectConfiguration.Configuration` is now called `HTTPClient.Configuration.RedirectConfiguration.Mode`
only two `Configuration`s left in the type name
* add redirect logger test
- Adding four new protocols:
- `HTTPExecutingRequest` a protocol representing an HTTP task that is executed on a ChannelHandler.
- `HTTPScheduledRequest` a protocol representing an HTTP task that is scheduled for execution, but in a waiting state (example: Waiting for an idle connection in the connection pool).
- `HTTPRequestExecutor` a protocol that can be used from the `HTTPExecutingRequest` abstracting away functionality that will normally be implemented by a `ChannelHandler`
- `HTTPRequestScheduler` a protocol that can be used from the `HTTPScheduledRequest` abstracting away functionality that will normally be implemented by a `ConnectionPool`
- An implementation of the `HTTPExecutingTask` and `HTTPScheduledRequest` called `RequestBag`. It implements our current API using the new protocols
Co-authored-by: George Barnett <gbarnett@apple.com>
Co-authored-by: Cory Benfield <lukasa@apple.com>
Fabian Fett
David Nadoba
